In a case in which a tubular-organ inside a living body, for example, a blood vessel of four limbs can be occluded by a foreign object and the blood flow can be disturbed, it can become a cause for inducing necrosis or intermittent claudication of finger tissues of a hand and a foot, which can be caused by ischemia. Therefore, there have been many proposed catheters provided with removal mechanisms for foreign objects (tubular-organ occluding objects).
For example, Japanese unexamined patent publication H11-347040 describes a catheter provided with a rotation cutter including a cylinder sleeve shaped body and a thread extending along a portion of the side surface of the aforesaid body. Japanese unexamined patent publication No. 2000-245741 describes a catheter provided with a cylindrical cutter including a thread extending along a portion of the side surface thereof and a saw blade which is arranged at an end portion and which is formed so as to extend from the center axis to the external side in the radial direction. Japanese unexamined patent publication No. 2004-514463 describes a catheter provided with a compound cutter assembly including a cutter whose distant diameter is fixed and a cutter assembly whose proximal diameter is adjustable. Japanese unexamined patent publication No. 2006-514577 describes a catheter provided with a blade edge assembly including a plurality of blade edge blades which present an appearance shape of approximately a round shape when seen from the axis line direction and of an elliptical or a circular truncated cone shape when seen from the lateral direction, and which are arranged radiation-symmetrically with respect to the center longitudinal axis and also, have differential blade edge surfaces.
However, the rotation surface of the cutters described in Japanese unexamined patent publication H11-347040, Japanese unexamined patent publication No. 2000-245741, Japanese unexamined patent publication No. 2004-514463, and Japanese unexamined patent publication No. 2006-514577 is approximately perpendicular with respect to the drive shaft and the blade edge of the cutter faces the tubular-organ wall, so that it can be easy for the lumen wall to be damaged. Also, since only a single cutter is provided, it may not be possible for the ground occluding object to be ground finely so as to be discharged easily to the outside of the body.
Exemplary embodiments of the present disclosure can, e.g., solve the problem involved in the existing technology mentioned above and can provide a catheter having a removal mechanism which excavates a tubular-organ occluding object inside a living body safely and also more efficiently, and which can also discharge the removed excavated object easily to the outside of the body.